MPA for lathes - the composition of emulsions, how to make your own hands
Any, even a novice metalworking specialist knows, what, performing turning work on the machine, be sure to use lubricating and cooling fluids (MPA). The use of such technical fluids (their composition may change) allows you to solve several important tasks simultaneously:
The use of ZOR in turning
- cooling of the cutter, actively heated during processing (in accordance, extension of its service life);
- improving the purity of the surface of the workpiece;
- increase the productivity of the metal cutting process.
Types used in the turning of ZOR
All types of coolant, used for turning work on the machine, are divided into two major categories.
Water-based coolant
Liquids of this category have good cooling characteristics, they absorb heat, is actively formed in the process of turning, and take it away from the cutting zone.
Oil-based coolant
Such liquids dissipate heat from the treatment area much worse, but provide excellent lubrication of the workpiece and tool surfaces.
Recommendations for the choice of coolant for specific operations and materials (click to enlarge)
Among the most common coolants, which are used in metal processing on lathes, the following can be noted.
- Soda ash solution (1,5%) in boiled water. This fluid is used when performing rough turning on a lathe.
- Water solution, which contains 0,8% soda and 0,25% sodium nitrite, which increases the anticorrosive properties of MPA. It is also used for rough turning on the machine.
- Solution, consisting of boiled water and trisodium phosphate (1,5%), almost identical in its cooling action of liquids, containing soda ash.
- Water solution, which contains trisodium phosphate (0,8%) and sodium nitrite (0,25%). It has improved anti-corrosion properties and is used when performing rough turning on lathes.
- Boiled water solution, containing special potassium soap (0,5–1%), soda ash or trisodium phosphate (0,5–0,75%), sodium nitrite (0,25%).
- Water-based solution, that contains 4% potassium soap and 1,5% soda ash. SOJ, which contain soap, used when performing drafting, as well as shaped turning on a lathe. Potassium soap can be replaced with any other if necessary, does not contain chloride compounds.
- Water-based solution, to which is added emulsol E-2 (2-3%) and soda ash (1,5%). MPA of this type is used in turning parts, to the cleanliness of the treated surface which are not subject to high requirements. With the use of such an emulsion it is possible to process workpieces on the machine at high speeds.
- Water solution, that contains 5-8% emulsol E-2 (B) and 0,2% soda or trisodium phosphate. With the use of such MPA on the lathe finishing turning.
- Water solution, which includes emulsol based on oxidized petrolatum (5%), soda (0,3%) and sodium nitrite (0,2%). You can use this emulsion when drafting, as well as finishing lathe on the machine, it allows to receive surfaces of higher purity.
- Oil-based liquid, which contains 70% industrial oil 20, 15% flaxseed oil of the 2nd grade, 15% gas. MPA of this composition is used in those cases, when high-precision carving is cut and workpieces are machined with expensive shaped cutters.
Options for the use of ZOR for lathes
- Sulfofrezol is a fatty oil, activated by sulfur. This lubricating and cooling fluid is used when performing turning with a small cross section. When performing rough work, characterized by active and significant heating of the tool and the workpiece, the use of such coolant can be harmful to the machine operator, as it emits volatile sulfur compounds.
- Solution, consisting of 90% sulfofrezole and 10% gas. This fluid is used when cutting threads, and also at deep drilling and finishing of preparations.
- Pure kerosene - used, when workpieces need to be machined on a lathe, made of aluminum and its alloys, and also at finishing with use of the fluctuating abrasive bars.
Features of application of lubricating and cooling liquids
That the use of ZOR was effective, a few simple rules should be considered. Consumption of such liquid (regardless, the emulsion is either an aqueous solution) must be at least 10-15 l / min.
It is very important to direct the coolant flow to that location, in which the maximum amount of heat is formed. Such a place when performing turning is the area, on which the chips are separated from the workpiece.
Test results of semi-synthetic water-soluble coolants Cimstar (click to enlarge)
From the very first moment of turning on the machine, the cutting tool begins to actively heat up, therefore, the MPA should be submitted immediately, and not after a while. Otherwise, cracks may form in the hot lathe cutter when it cools down sharply.
More recently, advanced cooling has been used, which involves the supply of a thin jet of coolant from the rear surface of the cutter. This method of cooling is especially effective in this case, when on a lathe with a tool from high-speed alloys need to process the workpiece of hard-to-machine materials.
It should be borne in mind, that MPAs are not used in turning materials, characterized by high fragility (cast iron, bronze, etc.), in which small shavings are formed. So shavings, mixing with lubricating and cooling liquid, can kill caliper elements, carriages and guide rails, which leads not only to their premature wear, but also failure.
